Here is a typical list of ingredients from the back of an "organic" shampoo bottle. with an abbreviated explanation as to what is in them.
Water (Aqua), Ammonium Lauryl Sulfate, Disodium Cocoamphodiacetate, Polyquaternium-39, Cocamine MEA, Stearic Acid, Dimethicone, Laureth-8, Succinoglycan, Glycol Distearate, Persea Gratissima (Avocado) Leaf Extract, Hydroxypropyl Guar, EDTA, Dimethlypabamidopropyl Lauryldimonium Tosylate, Propylene Glycol Stearate, Citric Acid, Fragrance (Parfum), DMDM Hydantoin. Not tested on animals.
Shampoo is basically detergent that strips out grease and dirt combined with a series of compounds that deposit a film onto the hair to add shine and body.
The detergents are the active component and raise the most health concerns. Detergent breaks up the bonds in water molecules so they dissolve the grease and dirt in your hair. Chemists describe such compounds as surfactants, because they reduce the surface tension of water. Add a drop of any detergent or shampoo to a drop of water and it will collapse. If mosquitoes try to land on water containing detergent they will fall through the surface of the water that they would normally walk on. Detergents have been used in the fight against malaria.
Detergents allow other chemicals to penetrate the skin more easily. Concerns have been expressed that because surfactants break down skin cells they can accelerate the ageing process. Some classes of surfactants – the nonylphenols – have been reported to interfere with the sexual development of wildlife.
The surfactants in this shampoo include Ammonium Lauryl sulfate, Laureth-8, Disodium Cocoamphodiacetate, Cocamine MEA
Cocoamphodiacetate is a surfactant derived from coconut oil with a very good toxilogical profile.
MEA (monoethylamine) is considered responsible for creating carcinogenic compounds that are absorbed through the skin. It is considered less dangerous than DEA (diethylamine) which has been banned in the US but is prevalent in Australia.
Other active chemicals that are not involved directly in the cleaning process include EDTA (ethylenediaminetetraacetic acid). It is used to soften the water by depositing mineral salts and locking them up in the shampoo foam. It also preserves the shampoo.
DMDM Hydantoin is a preservative that works by releasing formaldehyde into the shampoo to prevent mold, fungus and bacteria growing in it. Formaldehyde is a known carcinogen.
The second group of compounds are those left behind on the hair to replace the natural oils. These compounds are relatively inert, though their manufacture may cause industrial pollution.
Stearic Acid is made from blasting animal fat or saturated vegetable oils with water at high temperature and pressure and is used to give body to the shampoo. Propylene Glycol Stearate and Glycol Distearate are related compounds.
The addition of avacodo oil Persea Gratissima (Avocado) Leaf Extract into the mix does little to interfere with the underlying chemistry of the shampoo.
This shampoo contains Polyquaternium-39 which is cellulose derived from cotton, the silicone based Dimethicone as well as Succinoglycan and Hydroxypropyl Guar. Dimethlypabamidopropyl Lauryldimonium Tosylate is included to protect it from ultra violet radiation.
The third main group of compounds are used to add fragrance. This shampoo label simply labels that group as Fragrance. Over 4,000 chemicals are used to manufacture fragrances, 95 per cent of them derived from petroleum and 84 per cent which have never been tested for safety. Fragrances are considered trade secrets so do not have to be declared on product labels.
This is just one shampoo product. Conditioners contain a similarly strange mix of chemicals, and hair-colouring products that use synthetic dyes are probably even worse. For example, they may contain coal tar colours, listed on labels as FD&C and D&C, and made from bituminous coal. Or, they may contain phenylenediamine, another cancer causing agent. Some even contain lead. This is not only bad for you, but also the environment.